On Fri, Sep 05, 2014 at 10:29:26AM +0200, Alexander Graf wrote: > > > On 04.09.14 12:52, frank.blasc...@de.ibm.com wrote: > > From: Frank Blaschka <frank.blasc...@de.ibm.com> > > > > This patch adds GISA (Guest Interrupt State Area) support > > to s390 kvm. GISA can be used for exitless interrupts. The > > patch provides a set of functions for GISA related operations > > like accessing GISA fields or registering ISCs for alert. > > Exploiters of GISA will follow with additional patches. > > > > Signed-off-by: Frank Blaschka <frank.blasc...@de.ibm.com> > > That's a nice feature. However, please make sure that you maintain the > abstraction levels. > > What should happen is that you request an irqfd from FLIC. Then you > associate that irqfd with the PCI device. > > Thanks to that association, both parties can now talk to each other and > negotiate their GISA number space and make sure things are connected. > > However, it should always be possible to do things without this direct > IRQ injection. > > So you should be able to receive an irqfd event when an IRQ happened, so > that VFIO user space applications can also handle interrupts for example. > > And the same applies for interrupt injection. We also need to be able to > inject an adapter interrupt from QEMU for emulated devices ;). >
OK, assuming we are doing the vfio solution expoiting GISA would be a second step. Will take your feedback into account. THX! > > Alex > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
